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A Multimethod Analysis to Assess Locomotor Capabilities in Stem Tetrapods from Blue Beach (Tournaisian; Early Carboniferous), Nova Scotia

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A Multimethod Analysis to Assess Locomotor Capabilities in Stem Tetrapods from Blue Beach (Tournaisian; Early Carboniferous), Nova Scotia University of Calgary PRISM: University of Calgary's Digital Repository Graduate Studies The Vault: Electronic Theses and Dissertations 2020-01 A multimethod analysis to assess locomotor capabilities in stem tetrapods from Blue Beach (Tournaisian; Early Carboniferous), Nova Scotia Lennie, Kendra Ilana Lennie, K. I. (2020). A multimethod analysis to assess locomotor capabilities in stem tetrapods from Blue Beach (Tournaisian; Early Carboniferous), Nova Scotia (Unpublished master's thesis). University of Calgary, Calgary, AB. http://hdl.handle.net/1880/111587 master thesis University of Calgary graduate students retain copyright ownership and moral rights for their thesis. You may use this material in any way that is permitted by the Copyright Act or through licensing that has been assigned to the document. For uses that are not allowable under copyright legislation or licensing, you are required to seek permission. Downloaded from PRISM: https://prism.ucalgary.ca UNIVERSITY OF CALGARY A multimethod analysis to assess locomotor capabilities in stem tetrapods from Blue Beach (Tournaisian; Early Carboniferous), Nova Scotia by Kendra Ilana Lennie A THESIS SUBMITTED TO THE FACULTY OF GRADUATE STUDIES IN PARTIAL FULFILMENT OF THE REQUIREMENTS FOR THE DEGREE OF MASTER OF SCIENCE GRADUATE PROGRAM IN BIOLOGICAL SCIENCES CALGARY, ALBERTA JANUARY, 2020 © Kendra Ilana Lennie 2020 Abstract In vertebrate evolution the fin-to-limb transition was an important precursor to the diversification and radiation of terrestrial animals into novel environments. This transition began in the Devonian and continued through the Carboniferous and involved physiological and biomechanical changes. I used a multi-method approach to assess external and internal limb bone features to evaluate Early Carboniferous (Tournaisian) limb bones from Blue Beach and associated them with aquatic to terrestrial lifestyles. Tournaisian tetrapod material was collected at Blue Beach located near Hantsport, Nova Scotia, but much of it has not been formally described because the disarticulated and isolated tetrapod elements made identification to the species level difficult. In this thesis I described new morphotypes attributable to the family level which are used in the following chapters. Once the external morphology of the Blue Beach bones was described I compared them with the femora of extant aquatic, amphibious, and terrestrial tetrapods to evaluate which locomotor behaviour the fossil femora most resembled. I additionally examined cross-sectional bone profiles of Blue Beach tetrapod femora to infer lifestyle. Midshaft analyses relied on a single two-dimensional image to represent a dynamically structured bone so I also used a novel method for assessing three-dimensional trabecular data to qualitatively and quantitatively infer lifestyle from the Blue Beach femora. From the various analyses of internal and external bone morphology it was clear that external bone features of modern and early fossil tetrapod femora are dissimilar, which lead to difficulties in drawing conclusions based off external qualitative data. Internal data, from two-dimensional midshaft and three-dimensional trabecular structures, produced quantitative results that lead to the same conclusion, that the Blue Beach femora are consistent with those of aquatic animals. This implies that the initial diversification of the tetrapod body plans present in the Early Carboniferous was not the result of terrestrialization but appears to have preceded it. ii Preface This thesis is original, unpublished, work by the author, K. Lennie. iii Acknowledgments I would like to thank my supervisor Jason Anderson for helping me revise countless drafts and being patient with me for the last two and a half years. I would also like to thank my committee members Jessica Theodor, Sarah Manske, and Heather Jamniczky, whose support and suggestions (especially about trabecular bone analysis) was critical to the success of my project. I would like to thank NSERC for funding a Discovery Grant to Jason Anderson, which made this work possible. Additionally I’d like to thank Natalie Reznikov for training on the Bone Analysis module of Dragonfly ORS (Montreal), Katherine Ogdon and Tim Fedak for access to the specimens at the Nova Scotia Museum, Chris Mansky and Sonja Wood for access and preparation work on the specimens from the Blue Beach Fossil Museum, and Johanne Kerr for help finding and accessing elements from Eusthenopteron at Musée d’Histoire Naturelle de Miguasha. I want to thank my lab mates Jason Pardo, Conrad Wilson, James Campbell, Ramon Nagesan, Amber Whitbone, and Jamey Creighton, and Keith Johnstone for many informative and thought-provoking discussions, for listening to my constant complaining about muscles, and for providing feedback on many written applications and assignments. I would finally especially like to thank my parents for pushing me to do my best and supporting me in all my endeavours. iv Dedication I dedicate this thesis to all the girls and women who are defying traditional gender roles in science and sport. Never let anyone tell you should not or cannot do something because you are a girl. v Table of Contents Abstract ............................................................................................................................................ ii Preface ............................................................................................................................................ iii Acknowledgments........................................................................................................................... iv Dedication ........................................................................................................................................ v Table of Contents ............................................................................................................................ vi List of Tables .................................................................................................................................. ix List of Figures .................................................................................................................................. x Table of extant animals ................................................................................................................. xiv Abbreviations ................................................................................................................................. xv Institutional ................................................................................................................................ xv Anatomical ................................................................................................................................. xv Variables .................................................................................................................................... xv Chapter 1: Introduction ................................................................................................................. 1 Introduction .................................................................................................................................. 1 Historic hypotheses .................................................................................................................. 2 Romer’s Gap ............................................................................................................................ 2 Blue Beach ............................................................................................................................... 3 Historical proxies for locomotion ............................................................................................ 6 Predictions ................................................................................................................................. 11 Literature cited ........................................................................................................................... 13 Chapter 2: Descriptions of new tetrapod limb elements from Blue Beach, Nova Scotia ........... 23 Introduction ................................................................................................................................ 23 Abbreviations ............................................................................................................................. 23 Geological context ..................................................................................................................... 24 Material and Methods ................................................................................................................ 25 Results ........................................................................................................................................ 25 Humeri ................................................................................................................................... 25 Ulna ........................................................................................................................................ 26 Radii ....................................................................................................................................... 27 Femora ................................................................................................................................... 29 Fibulae ..................................................................................................................................
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